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Geodesic acoustic mode (GAM) is the finite frequency counterpart of zonal flow in toroidal plasmas, which could be excited by and regulate turbulence. This article reports a stationary eigenmode GAM at the inner side of the edge radial electric field contributing to an extreme high confinement plasma with $H_{98}\gt 1.3$ . Such GAM could be observed exclusively in the vicinity of the pedestal top, but not in the pedestal region itself, which represents a previously unreported phenomenon. The bicoherence analysis demonstrates a robust interaction between the GAM and quasi coherent mode (QCM). Statistical evidence indicates that GAMs with such characteristics display a proclivity for a large q _95 and low collisionality in all instances of H-mode accompanied by QCM. Based on the Gyro-kinetic simulation, the QCM is the low n trapped electron mode (TEM) and that the GAM is driven by TEM. Furthermore, the simulations show that the amplitude of GAM declines in conjunction with an increase in the collisionality, which is consistent with the experimental statistics. Additionally, the simulations demonstrate that the turbulent transport exhibits a corresponding decrease as GAM amplitude declines, implying that GAM and its interaction with the QCM would play an important role in the stability and confinement enhancement of such H-mode.

ABSTRACT: Chemically protected sodium butyrate (CSB) is a new kind of sodium butyrate. Our previous study found that 1,000 mg/kg of CSB had the potential capacity of improving growth performance and promoting early development of small intestine in broilers. This study aimed to investigate the effect of long-term antibiotics or CSB supplementation for intestinal microflora dynamical regulation in broilers. One hundred ninety-two 1-day-old Arbor Acres male broilers were randomly allocated into 3 dietary treatment (8 replicates per treatment) and fed with a basal diet (CON), a diet supplemented with the antibiotics (enramycin, 8 mg/kg and aureomycin, 100 mg/kg) (ANT), or a diet supplemented with 1,000 mg/kg of CSB, respectively. Results showed that dietary supplementation of CSB or ANT treatment elevated the weight gain and feed conversion ratio (FCR; P < 0.05), as compared with control (CON) group. Additionally, CON, CSB, or ANT administration dynamically altered the gut microbiota composition as time goes on. The increased presence of potential pathogens, such as Romboutsia and Shuttleworthia, and decreased beneficial bacteria such as Alistipes, Akkermansia, and Bacteroides were verified in new gut homeostasis reshaped by long-term antibiotics treatment, which has adverse effects on intestinal development and health of broilers. Conversely, CSB supplementation could dynamically enhance the relative abundance of Bacteroides, and decrease Romboutsia and Shuttleworthia in new microflora, which has positive effects on intestinal bacteria of broilers compared with CON group. Meanwhile, CSB supplementation was significantly increased the concentration of propionic acid and total short chain fatty acids (total SCFA; P < 0.05) in comparison with CON and ANT groups. Moreover, CSB treatment significantly increased anti-inflammatory and antioxidative capacities (P < 0.05) of broilers compared with ANT group. Taken together, we revealed characteristic structural changes of gut microbiota throughout long-term CSB or ANT supplementation in broilers, which provided a basic data for evaluating the mechanism of action affecting intestinal health by CSB or ANT administration and CSB as an alternative to antibiotics in the broilers industry.

In this study, a combination of acoustic emission (AE) method (AEM) and wave transmission method (WTM) is used to investigate the behaviors of AE and ultrasonic properties corresponding to initial fracturing in granitic rocks. The relationships of AE characteristics, frequency spectra, and spatial locations with crack initiation (CI) are studied. The anisotropic ultrasonic characteristics, velocity distributions in different ray paths, wave amplitudes, and spectral characters of transmitted waves are investigated. To identify CI stress, damage initiations characterized by strain-based method (SBM), AEM and WTM are compared. For granite samples, it shows that the ratio of CI stress to peak strength estimated by SBM ranges from 0.4 to 0.55, and 0.49–0.6 by WTM, which are higher than that of AEM (0.38–0.46). The CI stress identified by AEM indicates the onset of microcracking, and the combination of AEM and WTM provides an insight into the detection of rock damage initiation and anisotropy.

As ubiquitous structures in magnetized fusion plasmas, magnetic islands (MIs) would short-circuit adjacent magnetic flux surfaces and result in a reduced pressure gradient and fluctuations inside the island; it is widely accepted that due to the stabilizing of drift wave instability, the turbulence intensity inside MIs is much lower for larger islands. Here, we provide the first observations that strong turbulence could be generated inside a large radiation MI, which is probably driven by the electron temperature dip due to strongly localized impurity radiation. Moreover, the flow velocity inside the MI is strongly correlated with the turbulence intensity, and the impurity concentration rate suddenly increases as the flow velocity reaches a threshold value, strongly suggesting that turbulence and flow inside the island play important roles in trapping heavy impurities and sustaining radiative MIs.

Sulfur (S) regarded as the fourth key element is mainly taken by the plant roots. However, some plants can also absorb atmospheric sulfides, which may be of great importance for ameliorating the environment and for farming as a green organic S fertilizer used to balance insufficient soil S content for intensive cultivation in China; H2S and mainly SO2 are emitted to air as a result of the rapid industrialized and economic development. Globe amaranth (Gomphrena globosa L.) might be one of the plants that can use atmospheric sulfides for its growth. Therefore the effects of sulfate deprivation from root on its growth, S status and other elements concentration under hydroponic culture were explored firstly. Based on measurements of plant growth, biomass, nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), S, iron (Fe), manganese (Mn), copper (Cu), zinc (Zn), boron (B), and molybdenum (Mo) concentration, the results showed that S concentration in flower, shoot and root of plant without root sulfate supplied was increased with plant growth and development, symptoms of S deficiency disappeared and other elements concentration in plant tended to be nearly the same as the root sulfate-supplied plants. The interesting results might imply that globe amaranth may be able to live on the atmospheric sulfides as sulfur source.

By analyzing large quantities of discharges in the unfavorable ion drift direction, I-mode operation has been confirmed in the Experimental Advanced Superconducting Tokamak. During the L-mode to I-mode transition, the energy confinement is improvement substantially by the formation of a high-temperature edge pedestal, while the particle confinement remains almost identical to that in the L-mode. Similar with I-mode observations on other devices, the Er profiles obtained by the eight-channel Doppler backscattering system (DBS8) (Hu et al 2017 Rev. Sci. Instrum. 88 073504) show a deeper edge Er well in the I-mode than that in the L-mode. Additionally a weak coherent mode (WCM) with the frequency range of 40–150 kHz is observed at the edge plasma with the radial extent of about 2–3 cm. WCM could be observed in both density fluctuation and radial electric field fluctuation, and the bicoherence analyses showed significant couplings between WCM and high frequency turbulence, implying that the Er fluctuation and the caused flow shear from WCM should play an important role during I-mode operation. In addition, a low-frequency oscillation with a frequency range of 5–10 kHz is always accompanied with WCM, where the geodesic acoustic model intensity decreases or disappears. The evidence shows that the a low-frequency oscillation may be a novel kind of limited cycle oscillation but further investigation is needed to explain the new properties such as the harmonics and obvious magnetic perturbations. [ABSTRACT FROM AUTHOR]

The geodesic acoustic mode (GAM) has been observed for the first time in EAST H-mode operation using Doppler backscattering (DBS) systems. The poloidal and toroidal symmetries of the radial electric field (Er) fluctuation (m  =  0 and n  =  0) have also been demonstrated. Using the multichannel DBS system, the GAM frequencies at different radial locations have been investigated, with observations showing that H-mode GAM acts as a radial coherent eigenmode, rather than a continuum of frequencies in L-mode. The intermittency of GAM is observed in both L-mode and H-mode. The interplay between the background density fluctuations and the GAM intensity is revealed. The bicoherence analysis is also used to verify the presence of the nonlinear interaction between the GAM and background turbulence. [ABSTRACT FROM AUTHOR]

Phosphatase and tensin homologue (PTEN) protein levels are critical for tumor suppression. However, the search for a recurrent cancer-associated gene alteration that causes PTEN degradation has remained futile. In this study, we show that Importin-11 (Ipo11) is a transport receptor for PTEN that is required to physically separate PTEN from elements of the PTEN degradation machinery. Mechanistically, we find that the E2 ubiquitin-conjugating enzyme and IPO11 cargo, UBE2E1, is a limiting factor for PTEN degradation. Using in vitro and in vivo gene-targeting methods, we show that Ipo11 loss results in degradation of Pten, lung adenocarcinoma, and neoplasia in mouse prostate with aberrantly high levels of Ube2e1 in the cytoplasm. These findings explain the correlation between loss of IPO11 and PTEN protein in human lung tumors. Furthermore, we find that IPO11 status predicts disease recurrence and progression to metastasis in patients choosing radical prostatectomy. Thus, our data introduce the IPO11 gene as a tumor-suppressor locus, which is of special importance in cancers that still retain at least one intact PTEN allele. [ABSTRACT FROM AUTHOR]